In many types of flat panel display devices, Liquid Crystal Display (LCD) has features of small size, low power consumption, and low manufacturing costs, zero radiation, etc., and thus currently occupies leading position in the flat panel display market.
COF (Chip on Film) is a type of driving unit used in LCD. It is usually bonded to the edge of a liquid crystal panel by a means of hot pressing. As display technology continues to evolve, narrow bezel display products have attracted a large number of consumers because of their better visual experience. In order to obtain a narrow bezel liquid crystal display device, it is usually necessary to bend the COF from the lateral side of the LCD panel to the back of the backlight module to reduce the space of the side frame occupied by the COF.
In the conventional technology, after the chip on the backside of the backlight module is bent, the driver chip is on the side of the COF closer to the backlight module. During the operation of the LCD device, the driver chip itself generates more heat radiation, and the backlight module also generates a large amount of heat radiation. Since the driver chip faces toward the backlight module, the distance between the two is small, and accumulation of the thermal radiation generated by the backlight module and the driver chip to cause the temperature of the driver chip to be too high. Driver chip is an important part of the signal transmission and processing, and the temperature being too high usually affects the stability of work performance, results in reduced reliability of the driver chip, and even leads to damage on the driver chip due to overheating, SUMMARY
In view of the above issues, the present invention provides a LCD device that can reduce influences of the thermal radiation generated by the backlight module on the driver chip so as to enhance reliability of the driver chip.
To achieve the purposes, an objective of the present invention is to provide a liquid crystal display (LCD) device, comprising: a backlight module, comprising a light emitting surface and a back surface opposite to the light emitting surface; a liquid crystal panel, disposed on the light emitting surface of the backlight module, wherein a signal binding end is disposed on a front surface, away from the backlight module, of the liquid crystal panel; and a chip on film (COF), comprising a flexible circuit board, and a binding part and a driver chip disposed on a first surface of the flexible circuit board, wherein the flexible circuit board is connected to the signal binding end through the binding part and is bent extendedly to the back surface of the backlight module; wherein in the region of the flexible circuit board extendedly bending at the back surface of the backlight module, the first surface of the flexible circuit board comprises a first area facing away from the backlight module, and the driver chip is connected to the first area.
Wherein the COF comprises a flexible circuit board, and the binding part comprises a first binding part and a second binding part; the first binding part is disposed on a first end of the flexible circuit board in order to electrically connect the flexible circuit board to the signal binding end, the second binding part is disposed on a second end of the flexible circuit board in order to electrically connect the flexible circuit board to a printed circuit board, and the driver chip is disposed between the first binding part and the second binding part on a signal transmission pathway.
Wherein two or more bending portions are disposed between the first end and the second end of the flexible circuit board; and the two or more bending portions allow the flexible circuit board to bend and extend in an S shape to the back surface of the backlight module.
Wherein a first bending portion and a second bending portion are disposed between the first end and the second end of the flexible circuit board, and the first area is defined as an area between the second bending portion and the second end of the first surface and faces away from the backlight module.
Wherein the first binding part is connected to the signal binding end through a first anisotropic conductive film, and the second binding part is connected to the printed circuit board through a second anisotropic conductive film.
Wherein the COF comprises a plurality of sequentially connected flexible circuit boards; first surfaces of two of the connected adjacent flexible circuit boards are oriented oppositely, at least one of the flexible circuit board is arranged at the back surface of the backlight module and a first surface of the at least one of the flexible circuit board faces away from the backlight module to form the first area.
Wherein the COF comprises a first flexible circuit board and an interconnected second flexible circuit board, and the binding part comprising a first binding part, a second binding part, a third binding part and a fourth binding part; the first binding part is disposed on a first end of the first flexible circuit board to electrically connect the first flexible circuit board to the signal binding end; the second binding part is disposed on a second end of the first flexible circuit board to electrically connect the first flexible circuit board to the second flexible circuit board; the third binding part is disposed on a first end of the second flexible circuit board to electrically connect the second flexible circuit board to the first flexible circuit board; the fourth binding part is disposed on a second end of the second flexible circuit board to electrically connect the second flexible circuit board to a printed circuit board; and a first surface of the second flexible circuit board faces away from the backlight module, and the driver chip is disposed on a first surface of the second flexible circuit board.
Wherein a first bending portion is disposed between the first end and the second end of the first flexible circuit board, the first bending portion allows the second end of the first flexible circuit board extending to the back surface 1b of the backlight, and the second flexible circuit board is flatly connected to the second end of the first flexible circuit board.
Wherein the first binding part is connected to the signal binding end through a first anisotropic conductive film, the second binding part is interconnected with the third binding part through a second anisotropic conductive film, and the printed circuit board is connected to the fourth binding part through a third anisotropic conductive film.
Wherein the COF comprises a gate-COF for signal scanning and a source-COF for data signal providing.
As the LCD device provided in the embodiment of the present invention, the COF is bent extend to the back surface of the backlight module, and the driver chip is on the COF facing away from the backlight module. Thus the distance of the driver chip and the backlight module is increased, and under a condition that beneficial to the design of the narrow bezel, the issue of bad work performance due to overheating the driver chip can also be avoided, Reliability of the driver chip is therefore increased.